Electric heating and regulating device for incubators



W. G. NELSON.-

ELECTRIC HEATING AND REGULATING DEVICE FOR INCUBATORS.

I APPLICATION man JAN. 15, 1920.

1 ,388,966, I Patented Aug. 30, 1921.

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PATENT OFFICE,

4 WILLIAM Gr. NELSON, OF RACINE, WISCONSIN.

ELECTRIC HEATING AND REGULATING DEVICE FOR INCUBATORS.

Specification of Letters Patent.

Patented Aug. 3@, 1921,

Application filed January 15, 1920. Serial No. 351,520.

T all w ham it may concern Be it known that I, WILLIAM G. NELSON, acitizen of the United States, and resident of Racine, in the county ofRacine and State of Wisconsin, have invented new and useful Improvementsin Electric Heating and Begulating Devices for Incubators, of which thefollowing is a description, reference being had to the accompanyingdrawings, which are a part of this specification.

The present invention relates to certain new and useful improvements inincubators and refers more particularly to the heating means therefor.

thermostatically controlled electric heating means operable toautomatically open and close the circuit to control the heat within theincubator upon temperature changes therein.

Another object of my invention is to provide an ether filledthermostatic expansion chamber connected with the circuit controlledmember whereby changes in the temperature of the incubator will betransmitted to said chamber in the form of a movement to or from thecircuit closing position according to the change in temperature. .s

A further object of this invention is to '30 provide means for adjustingthe degree of heat at which the circuitis opened or closed.

A still further object of this invention is to provide a compact heatingunit for incubators which may be readily embodied, in

incubators now in use or in incubators at the time of manufacture;

)Vith the above and other objects in view which will appear as thedescription pro ceeds, my invention resides'in the novel construction,combination and arrangement of parts substantially as hereinafterdescribed and more particularly defined by the appended claims, it beingunderstood that such changes in the precise embodiment of thehereindisclosed invention may be made as come within the scope of theclaims.

In the accompanying drawing I have illustrated one complete example ofthe physical embodiment of my invention constructed according to thebest mode I have so far devised for the practical application of theprinciples thereof, and in which:

Figure 1 is a perspective view of an in- One object of my invention isto provide" cubator equipped with my improved form of heating unit, and

Fig. 2 is an enlarged view part in section and part in elevation of mycomplete heating unit.

Referring now more particularly to the accompanying drawing, the numeral5 designates an incubator of any desired style or construction havingdisposed therein suitable heating elements 6 having electrical feedwires '7 connected therewith. The feed wires 7 are connected with asuitable source of supply by means of an electric cord 8 adapted to haveits end 9 engaged with a main feed line.

One of the feed wires 7 is broken and has the. ends thereof connected toa detachable trical energy supplied to the heating elements. Thisopening and closing of the electrical circuit at the'contacts 11 iscontrolled automatically upon changes in the temperature within theincubator.

The means I employ for opening and closing the electrical circuitconsists of a member 12 medially pivoted as at 13 between two bracketmembers 14 secured to the incubator wall 5' and having"a contact membersecured to one end, which includes an insulating block 15 having acopper plate 16 secured thereto for engagement with the contacts 11, andan adjustable counterbalance weight 17 carried by its other end. Securedto the member 12 adjacent its pivot 13 is a disk plate 18 havingadjustably secured therein a threaded screw 19 which has itslongitudinal axis to one side of the pivot 13'between said pivot'and thecontact closing member.

The adjusting screw 19 is connected with a thermostatic device by meansof a rod 20 having its ends tapered and' its upper end disposed in atapered opening in the lowerend of the adjustable screw, and its otherend engaged in a tapered opening in a boss 21 secured to the upper plateof a double diaphragm 22 forming a thermostatic expansion chamber 23.The rod 20 passes into the incubator through a tube 24 having its upperend secured to the brackets 14-..

The double diaphragm has its under disk secured to one arm 25 of a Ushaped bracket member 26 having its other arm 27 removably secured tothe tube 24: as at 28. The thermostatic expansion chamber 23 ispreferably filled with ether to make the same especially sensitive totemperature-changes, and when the heat within the incubator rises abovea predetermined degree the expansion of the ether within the chamber 23will cause the diaphragm disk to expand and, through the rod 20, movethe member 20 on its pivot and raise the plate 16 from engagement withthe contacts 11. \Vhen the temperature within the incubator falls belowa predetermined degree, the ether within the chamber 23 will contractand permitthe member 12 to move on its pivot and the plate 16 to restupon the contacts 11 and complete the electrical circuit.

The temperature at which the electrical circuit will be opened or closedis controlled by means of the adjustable screw 19 as will be obvious.The counter balanced weight 17 is employed to permit the balancing ofthe member 12 so that the end of the member carrying the circuit closingplate 16 will fall when the double diaphragm is contracted.

lVhat I claim as my. invention is:

1. A heating unit comprising a heating element, an electrical circuitconnected with the heating element and having a break therein, and meansfor automatically opening and closing the break in said circuitincluding a pivoted lever, a circuit closing plate carried thereby andmovable to close the break in said circuit, and a. thermostaticexpansion chamber adjustably connected with the lever to impart amovement thereto upon the temperature changes.

2. A heating unit comprising a heating element, an electrical circuitconnected with the heating element and having a break therein, and meansfor automatically opening and closing the break in said circuitincluding a counter-balanced pivoted lever, a circuit closing platecarried thereby and movable to close the break in said circuit, and athermostatic expansion chamber adjustably connected with the lever to;impart Leeaeee a movement thereto upon the temperature changes.

3. An incubator including means for maintaining the same at a constanttemperature comprising a heating element, an electrical circuitconnected therewith and having a break therein terminating in twocontact points, a medially pivoted member, an insulated block carried byone endJoiE said member, a conductor plate carried by said insulatingblock and adapted to engage said contact points and close the electricalcircuit, an adjustable counter-balance carried by the other end of saidmember, an adjusting screw carried by said member between its pivot andsaid insulating block, bracket members between which said pivoted memberis secured, a U shaped bracket carried by said other bracket member, adouble diaphragm forming a thermostatic expansion chamber securedto onearm of said. U shaped bracket member, and means connecting said doublediaphragm With said adjustable screw whereby the contraction orexpansion of said thermostatic expansion chamber due to changes intemperature will be imparted to said pivoted member to open and closethe circuit.

4. A device of the class described, comprising a medially pivoted lever,a counterbalance weight carried by one end of said lever, a circuitclosure carried by the other end of said lever, a thermostatic expansionmember, and means adjustably connecting said member with the lever andincluding an adjustable screw carried by said lever and a rod having oneend engageable with the adjustable screw and its otherend engageablewith said expansion member.

5. A device of the class described, comprising a medially pivoted lever,a counterbalance weight carried by one end of said lever, a circuitclosure carried by the other end of said lever, a plate carried by saidlever to one side of its pivot and having a threaded opening therein, ascrew bolt having its shank adjustably mounted in said opening andhaving a notched recess in its lower end, an expansion member, and a rodhaving one end engaged with said expansion member and its other endengaged in the recess of said bolt to impart the movements of saidexpansion member to said lever.

In testimony whereof I aflix my signature.

WILLIAM G. NELSON.

